Pitch

Introduction

This module provides classes and methods for handling musical pitch data. It includes the _PSet private class, which extends the core _Set class to specifically manage pitch-related operations. The module also provides the Chord and Scale classes for handling chords and scales, respectively.

_PSet Class

The _PSet class extends the core _Set class to add pitch-specific functionality. It adds properties and methods for handling MIDI pitches, intervals, root notes, and frequency conversions. This class serves as the base for more specialized pitch classes like Chord and Scale.

_PSet.__init__(values: Sequence[Real], offset: Real) → None

Representation of a list of notes

Parameters:

• values (ArrayLike) – Notes.

• offset (Numeric) – Offset for the notes.

Example:

>>> a = _PSet([9, 0, 7, 1], 60)
>>> print(a)
_PSet = [69, 60, 67, 61]

_PSet.pitches

Return the absolute pitches in MIDI format.

Returns:

list of pitches

Return type:

list[Numeric]

Example:

>>> a = _PSet([9, 0, 7, 1], 60)
>>> print(a.pitches)
[69, 60, 67, 61]

_PSet.intervals

Returns the intervals of the sequence. NB: need the root note!!

Returns:

list of intervals

Return type:

list[Numeric]

Example:

>>> a = _PSet([9, 0, 7, 1], 60)
>>> print(a.intervals)
[9, 0, 7, 1]

_PSet.root

Return the root note

Returns:

root note

Return type:

int

Example:

>>> a = _PSet([9, 0, 7, 1], 60)
>>> print(a.root)
60

_PSet.to_freq(A4: float = 440) → list[float]

Convert midi pitches in frequency

Parameters:

A4 (float) – A4 tuning in frequence

Returns:

list of frequencies

Return type:

list[float]

Example:

>>> a = _PSet([69, 60, 57, 81])
>>> print(a.to_freq())
[440.0, 261.6255653005986, 220.0, 880.0]

_PSet.to_midi(a4: float = 440) → _PSet

Convert frequencies in midi pitches :param a4: A4 tuning in frequence :type a4: float :return: new Self :rtype: Self

Example:

>>> a = _PSet([440, 265, 220, 880])
>>> print(a.to_midi())
 _PSet = [69.0, 64.0, 62.0, 81.0]

classmethod _PSet.from_freq(freqs: list[float], a4: float = 440.0) → Self

Create new pitch class form list of frequencies

Parameters:

• freqs (list[float]) – list of frequencies

• a4 (float) – A4 tuning in frequence

Returns:

new pitch istance

Return type:

Self

Example:

>>> a = [440, 261, 220, 880]
>>> b = _PSet.from_freq(a)
>>> print(b)
_PSet = [69, 60, 57, 81]

_PSet.to_range(min: int, max: int) → Self

Move a list of notes to a specific range. If possibile without pitch change, otherwhise min if lower, max if higher.

Parameters:

• min (int) – min value of range

• max (int) – max value of range

Returns:

New Self

Return type:

Self

Example:

>>> a = _PSet(ScaleModel.maj, 60)
>>> b = a.to_range(36, 48)
>>> print(b)
_PSet = [36, 38, 40, 41, 43, 45, 47]

_PSet.micro_quanta(tone_div: int) → Self

Quantazie to nearest tone division

Parameters:

tone_div (int) – tone subdivision

Returns:

self

Return type:

Self

Example:

>>> a = _PSet([60.1, 62.3, 63.7, 64.5, 65.9, 66.2, 67.8])
>>> b = a.micro_quanta(4)
>>> print(b)
_PSet = [60.0, 62.25, 63.75, 64.5, 65.75, 66.25, 67.75]

_PSet.scale_quanta(scale: ScaleModel | Sequence[Real], unique: bool = False) → Self

Quantize to nearest note of scale :param scale: scale model or list of intervals :type scale: ScaleModel | ArrayLike :param unique: if True, return only one note for each pitch class, default False :type unique: bool :return: new Self :rtype: Self

Example:

>>> a = _PSet([60, 62, 63, 64, 65, 66, 67])
>>> b = a.scale_quanta(ScaleModel.maj, True)
>>> print(b)
_PSet = [60, 62, 64, 65, 67]

Chord Class

The Chord class represents a musical chord as a collection of pitches. It extends _PSet and provides methods for creating chords from models, inverting chords, and manipulating chord notes. Chords are defined by a list of intervals relative to a root note, and they inherit all operations from the _Set class.

from musicnpy import Chord, ChordModel

# Create a chord by specifying intervals and root
c = Chord([0, 4, 7], 60)
print(c.pitches)  # [60, 64, 67]

# Create a chord from a model
maj = Chord.new(ChordModel.maj, 60)
print(maj)

Chord.__init__(notes: Sequence[Real] = [0, 4, 7], root: Real = 0) → None

Rapresentation of Chord

Parameters:

• notes (ArrayLike) – List of intervals or pitches

• root (Numeric) – Root note

Example:

>>> a = Chord([0, 4, 7], 60)
>>> print(a)
Chord = [60, 64, 67]

classmethod Chord.new(model: ChordModel, root: Real = 0) → Chord

Create a Chord from ChordModel database

Parameters:

• model (ChordModel) – ChordModel istance

• root (Numeric) – Root note

Returns:

new Chord instance

Return type:

Chord

Example:

>>> a = Chord.new(ChordModel.aug, 60)
>>> print(a)
Chord = [61, 65, 69]

Chord.n_inversion(pos: int) → Chord

Inversion of chord

Parameters:

pos (int) – position of inversion

Returns:

New Chord

Return type:

Self

Example:

>>> a = Chord([0, 1, 2, 3])
>>> b = a.n_inversion(2)
>>> print(b)
Chord = [2, 3, 12, 13]

Chord.first_inv

First inversion

Returns:

New Chord

Return type:

Chord

Example:

>>> a = Chord.new(ChordModel.maj, 60)
>>> b = a.first_inv
>>> print(b)
Chord = [64, 67, 72]

Chord.second_inv

Second inversion

Returns:

New Chord

Return type:

Chord

Example:

>>> a = Chord.new(ChordModel.maj, 60)
>>> b = a.second_inv
>>> print(b)
Chord = [67, 72, 76]

Chord.drop(pos: int) → Chord

Drop note at specific position by single octave, up or down

Parameters:

pos (int) – position of drop

Returns:

New Chord

Return type:

Chord

Example:

>>> a = Chord([0, 1, 2, 3, 4]).drop(3)
>>> print(a)
>>> Chord = [0, 1, -10, 3, 4]

Chord.drop2

Drop the second highest note

Returns:

New Chord

Return type:

Chord

Example:

>>> a = Chord([0, 4, 7, 10], 60).drop2
>>> print(a)
>>> Chord = [60, 64, 55, 70]

Chord.drop3

Drop the third highest note

Returns:

New Chord

Return type:

Chord

Example:

>>> a = Chord([0, 4, 7, 10], 60).drop3
>>> print(a)
>>> Chord = [60, 52, 67, 70]

Chord.octaver(octaves: Sequence[Real]) → Chord

Shif by octaves specific pitches of chord

Parameters:

octaves (ArrayLike) – array of octave

Returns:

New Chord

Return type:

Self

Example:

>>> a = Chord([60, 62, 63])
>>> b = a.octaver([0, 1, -1])
print(b)
Chord = [60, 74, 51]

Scale Class

The Scale class represents a musical scale as an ordered collection of pitches. It extends _PSet and adds harmonic and diatonic degree functionality. Scales can be created from interval patterns or from scale models in the database.

from musicnpy import Scale, ScaleModel

# Create a scale by specifying intervals and root
s = Scale([0, 2, 4, 5, 7, 9, 11], 60)
print(s.pitches)  # [60, 62, 64, 65, 67, 69, 71]

# Create a scale from a model
maj = Scale.new(ScaleModel.maj, 60)
print(maj)

Scale.__init__(intervals: Sequence[Real], root: Real = 0, harmo: Sequence[Real] = None) → None

Rappresentation of a musicale Scale

Parameters:

• intervals (ArrayLike) – List of intervals

• root (Numeric) – Root note

• harmo (ArrayLike) – List of Chord class or ChordModel

Example:

>>> a = Scale([0, 2, 4, 5, 7, 9, 11], 60)
>>> print(a)
Scale = [60, 62, 64, 65, 67, 69, 71]

classmethod Scale.new(model: ScaleModel, root: int = 60) → Scale

Create a Scale from ScaleModel database

Parameters:

• model (ScaleModel) – scale model

• root (int) – root note

Returns:

new istance

Return type:

Scale

Example:

>>> a = Scale.new(ScaleModel.maj, 60)
>>> print(a)
Scale = [60, 62, 63, 65, 67, 68, 70]

Scale.diatonic

List of ints

Returns:

Description

Return type:

list[int]

Example:

>>> a = Scale([0, 2, 3, 5, 7, 8, 10], 76)
>>> print(a.diatonic)
[1, 2, 3, 4, 5, 6, 7]

Scale.harmonize

List of chords fo the scale.

Parameters:

self – Description

Returns:

Description

Return type:

list

Spectra Class

Spectra allow to create a collection of frequencies, that can be used to create a chord or a scale. It also provied some class method for create spectra series.

from musicnpy import Spectra

# Create a spectra by specifying frequencies
s = Spectra([440, 880, 1320])
print(s.frequencies)  # [440, 880, 1320]

Spectra.__init__(freqs: Sequence[Real]) → None

Rappresentation of a spectra

Parameters:

freqs (ArrayLike) – list of frequencies

classmethod Spectra.harm_series(fond: float, lenght: int, factor: float = 1) → Spectra

Create harmonic series from fondamental frequency.

Parameters:

• fond (float) – fondamental frequency

• lenght (int) – number of partials

• factor (float) – factor of partials, default 1 (harmonic series)

• a4 (float) – A4 tuning in frequence

Returns:

new Spectra

Return type:

Spectra

Example:

>>> a = Spectra.harm_series(55, 8, 1)
>>> print(a)
Spectra = [33.0, 45.0, 52.0, 57.0, 61.0, 64.0, 67.0, 69.0]

Spectra.ring_mod(mod: float) → Spectra

Ring modulation of spectra with carrier

Parameters:

• carrier (_PSet) – carrier for ring modulation

• mod (float) – modulation index

Returns:

new Spectra

Return type:

Spectra

Example:

>>> a = Spectra.harm_series(55, 8, 1)
>>> b = a.ring_mod(Scale.new(ScaleModel.maj, 60), 0.5)
>>> print(b)
Spectra = [15.0, 22.5, 26.0, 28.5, 30.5, 32.0, 33.5, 34.5]

classmethod Spectra.to_ring_mod(carrier: Chord | Scale | _PSet, mod: float, a4: float = 440) → Spectra

Ring modulation of a carrier with modulation index

Parameters:

• carrier (Chord | Scale | _PSet) – carrier for ring modulation

• mod (float) – modulation index

• a4 (float) – A4 tuning in frequence

Returns:

new Spectra

Return type:

Spectra

Example:

>>> a = Chord([0, 4, 7], 60)
>>> b = Spectra.to_ring_mod(a, 21.234)
>>> print(b)
Spectra = [418.61, 481.83, 523.25, 461.77, 440.0, 502.46]